In order to study tensile mechanical behaviors of reinforcements, air tensile tests were carried out on MAC geogrid, 70RE and 80RE geogrid, gabion wire, gabion meshes of different dimensions and mesh-types. Main mechanical indexes of these reinforcements were obtained, and discussions were made on tension distribution along reinforcements and calculating formula for unit elongation of gabion mesh. In addition, standard linear three-element model, nonlinear three-element model and Kawabata improved model were taken in for tensile curves simulation. The results show that MAC geogrid shows high strength characteristic. Most of ribs of 70RE geogrid or 80RJE geogrid rupture simultaneously. Gabion wire yields at low stain. Tensile curve of gabion mesh shows zigzag shape, and the PVC covered-layer has no effect on its tensile strength. Tensile load can distribute along gabion mesh quite uniformly, and there will not be obvious stress concentration. Unit elongation of gabion meshes are determined by hexagonal shape, sectional area of gabion wire, secant deformation modulus, failure strength, and so on. Standard linear model and nonlinear model have good simulation effects on MAC geogrid, gabion wire and gabion mesh, and Kawabata improved model can simulate MAC geogrid quite well.%为研究加筋土筋材拉伸力学特性,选取MAC土工格栅、70RE和80RE土工格栅、格宾金属丝以及不同型号和尺寸的格宾网进行拉伸试验,获得这些筋材的主要力学性能指标,探讨筋材受力集中情况以及格宾网伸长率计算方法.并采用标准线性三元件模型、非线性三元件模型和Kawabata改进模型对各种筋材拉伸曲线进行模拟.研究结果表明:MAC土工格栅表现出显著的高强度特性,70RE和80RE土工格栅的破坏模式为多条筋肋同时崩断;格宾金属丝表现为低应变屈服,格宾网的拉伸曲线呈现出锯齿状,且PVC包裹层对其抗拉强度影响不大；格宾网在拉伸荷载作用下能较好地调整网丝的受力状况,不会产生很大的受力集中现象；格宾网的伸长率取决于六边形的形状特点、格宾网丝的截面面积、割线变形模量、破坏强度等;标准线性三元件模型、非线性三元件模型对MAC土工格栅、格宾金属丝和格宾网拉伸曲线模拟效果良好,Kawabata改进模型对MAC土工格栅模拟效果良好.
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